My main monitor is a 27" 1440p 165Hz monitor and I use a 24" 1080p 60Hz monitor as a secondary display. There I have LittleNavMap, SimToolKitPro, OBS and Edge open. I really can’t miss this secondary monitor anymore. It’s so convenient.
I also use an older tablet with Touch Portal for easy switching between different camera views and/or setting airplane lights or other controls. And when I just booted my PC, I start every app I need for MSFS via Touch Portal.